The present invention is directed to a roll-up partition system assembly which has a protective partition for covering a window or door opening that may be rolled up into a housing when not in use. More particularly, the present invention is directed to a modular assembly implementing an improved tension adjustment mechanism for roll-up partition systems. The embodiments disclosed herein illustrated the various aspects of the present invention applied to one particular type of roll-up partition system: rolling protective shutters formed from a plurality of interconnected slats. It will be apparent to those of ordinary skill in the art that the present invention has application in other systems wherein a partition member is coupled to and rolls up onto a support member within a housing, such as roll-up doors, roll-up grills, roll-up gates and the like. The application of the present invention to the various types of roll-up partition systems is contemplated by the inventor.
One type of roll-up partition system is a rolling protective shutter. Rolling protective shutters are conventional and are used to provide protection against extreme weather conditions and to deter theft, for example. One such rolling protective shutter is disclosed in U.S. Pat. No. 4,345,635 to Solomon. As shown in FIGS. 1 and 2 of that patent, the Solomon shutter is composed of a plurality of elongate slats, each of which has a pair of circular ribs attached to its sides. The slats are interconnected by a plurality of elongate hinges, each of which has a pair of circular apertures in which the circular ribs of the slats are disposed. When the Solomon shutter is unrolled to its protective position, each of the slats in the shutter is disposed vertically with the ends of the slats disposed with guide channels or side tracks on either side of the opening. When not in use, the Solomon shutter may be rolled up into a housing disposed at the upper end of the protective shutter.
Another type of rolling protective shutter is disclosed in U.S. Pat. No. 5,365,990 to Ueda. As shown in FIGS. 2 and 3 of that patent, the Ueda shutter is composed of a plurality of slats, each of which has an upper rearward hook extending longitudinally along the upper edge of the slat and a lower U-shaped recess extending longitudinally along the lower edge of the slat. The recess has a forward horizontal projection on a rear edge and extending longitudinally so that when the lower slat moves down under gravity, the hook of the lower slat bears on the horizontal projection of the upper slat. The Ueda shutter may be rolled up and unrolled in a similar manner as the Solomon shutter.
In rolling shutter systems such as the Solomon and Ueda shutters, a portion of the shutter must remain within the side tracks to prevent the shutter from completely rolling up onto the take-up roll within the shutter housing. In some applications, the bottommost slat has a projection, such as a handle, extending outwardly from the shutter. One way to stop the bottom of the shutter from entering the housing is to size the opening in the housing through which the shutter passes narrow enough so that the projection hits the housing. The bottom of the shutter will stop short of entering the housing, but in many installations the housing is fabricated from sheet metal that is easily bent after repeated impacts by the projection or if the shutter is rolled up too rapidly.
In another alternative for stopping the bottom of the shutter, metal braces are attached to the side tracks and extend inwardly into the opening so that they engage the projection as the shutter is rolled up. Although the braces are stronger than the sheet metal housing, the handle and the braces can be damaged from repeated metal-on-metal impacts. Both the projection and the braces can be bent, gouged or broken, thereby increasing the possibility that the entire shutter will roll up into the housing and causing deterioration of the appearance of the shutter system. Additionally, the shutter may make a loud bang when the metal projection impacts the metal braces. Therefore, there is a need for a better stopping mechanism that is reliable and adjustable, and will preserve the appearance of the shutter system.
The most common mounting application for shutter systems is a surface mount for the housing and shutter tracks on either the inside or the outside of the opening. In other mounting applications, the housing and side tracks are mounted between the walls or jambs that define the opening. In these applications, a recess mount may be used wherein the ends of the side tracks are mounted directly to the walls or jambs. However, if the walls or jambs are not plumb and flat, or if the dimensions of the opening are even slightly off, the side tracks may not mount flush against the wall or jamb, the shutter may get bound up in the tracks or, alternatively, come out of the tracks, or the shutter system may not fit within the opening.
In an alternative to recess mounts, angle mounts are used wherein L-shaped angle brackets are used to mount the side tracks to the walls or jambs. When angle mounts are used, the measurements are not as critical because the angle bracket acts as a trim spacer that hides the space between the side track and the wall or jamb. One drawback to the angle mounts versus the recess mounts is that the heads of the fasteners used to attach the angle brackets are visible. Visible fastener heads may be acceptable for shutter systems mounted to building exteriors, but they may not be desired in interior applications. Therefore, a need exists for a cover for the angle brackets that hides the heads of the fasteners and provides a finished appearance to the angle mounted shutter system.
Another type of rolling protective shutter is disclosed in U.S. Pat. No. 5,575,322 to Miller. As shown, the shutter assembly includes a shutter support member mounted for rotation in a shutter housing. A rolling shutter composed of a plurality of individual slats is coupled to the shutter support member so that the shutter can be rolled up onto the shutter support member. A pair of shutter tracks extend downwardly from either end of the shutter housing. When the shutter is in its unrolled position, the ends of the slats are disposed within the tracks.
In shutter assemblies such as the one disclosed in the Miller patent, the shutter housing is integrally connected to each of the shutter tracks by a nipple that extends downwardly from the housing. The shutter housing is pre-assembled with the shutter and shutter support member mounted therein. The nipple is inserted into a channel in the shutter track to prevent movement of the housing with respect to the shutter track. Once both shutter tracks are attached to the housing, the entire assembly is tilted up against the frame of the opening, and the shutter tracks and housing are anchored to the frame.
The procedure for assembling and mounting the shutter assemblies as described above is adequate for shutters that are relatively light-weight. However, in installations requiring larger, heavier shutters, previous shutter assemblies present reliability and safety concerns. For example, the shutter housings are typically fabricated from sheet metal that may not be strong enough to anchor the housing and shutter to the wall. The weight of the shutter causes the housing to pivot about points of intersection of the housing and tracks leaving only the nipple, which is not designed as a load bearing component, to resist the pivoting of the housing and shutter. A similar problem is encountered where the shutter cannot be anchored in studs and the shutter housing is anchored to drywall. Additionally, the fully assembled shutter assembly is top-heavy and awkward to mount to the wall. Until the shutter housing is anchored to the wall, the installers risk having the nipples break off and the housing and shutter crash down on them. Moreover, the cost of packing and shipping the shutter assemblies is increased because the container must accommodate the outwardly extending nipples, thereby increasing the size of the container. Therefore, a need exists for a modular shutter assembly that is stronger, easier and safer to install, and less costly to ship than previous shutter assemblies.
Roll-up partitions in general, and rolling protective shutters in particular, typically incorporate one or more torsion spring assemblies to assist in rolling and unrolling the shutters manually or by a powered opening device. In one arrangement, the assembly is a self-contained modular unit having a rod surrounded by a coiled torsion spring. One end of the rod includes a rod support that is rotatable about the rod, and a spring plate rigidly fixed to the rod and to the proximate end of the torsion spring to prevent rotation of the end of the torsion spring relative to the rod. The other end of the rod includes a spring drive that is rotatable about the rod and rigidly fixed to the other end of the torsion spring. The assembly is inserted into the shutter support member with one end of the rod rigidly fixed to the shutter housing. The rod support and spring drive engage the interior of and rotate with the shutter support member. When the shutter is unrolled, the torsion spring is wound tighter, thereby providing additional torque to assist in lifting and rolling the shutter onto the shutter support member. During normal operation of the rolling protective shutters, the torsion spring exerts a minimum torque when the shutter is in the rolled position and a maximum torque when the shutter is in the unrolled position.
During installation, the torsion spring is wound to an initial tension by winding the shutter and shutter support member around the rod prior to inserting the free end of the shutter into the shutter tracks. The free end of the shutter is inserted into the tracks and a retention mechanism retains the free end of the shutter within the tracks. If the tension on the torsion spring is too high or too low, the retention mechanism is removed and the shutter and shutter support member are wound or unwound to adjust the tension in the torsion spring. In this adjustment process, the amount of disassembly required is not insubstantial. Additionally, the tension in the spring is adjustable in increments of one full rotation of the shutter support member. In some applications, an acceptable torsion spring tension may only be attainable with a partial rotation of the shutter support member. Therefore, a need exists for an improved tension adjustment mechanism for torsion springs in rolling protective shutters that minimizes or eliminates the disassembly of the shutter assembly and allows tension adjustment in increments of less than a full rotation of the shutter support member.